Monitoring Antiretroviral Adherence to Improve HIV Treatment and Prevention
Christopher Gordon, PhD.
Division of AIDS Research
The aims of this initiative are to improve treatment for HIV/AIDS and HIV prevention by advancing: (i) Methods for real-time or prospective monitoring of oral ARV adherence (antiretroviral therapy [ART], pre-exposure prophylaxis [PrEP]); (ii) Timely and targeted delivery of interventions when adherence monitoring reveals deficits; and, (iii) Predictive models that estimate current risk of viral breakthrough or HIV infection for a given individual based on ART adherence monitoring and related data.
There remains no gold standard for behavioral assessments of ART adherence. Many assessment methods have been examined in the context of HIV treatment, including self-reports, pharmacy refill, announced and unannounced pill counts, and electronic drug monitoring. The validity and precision of these tools vary, and each contains advantages and disadvantages. Any assessment approach for ART adherence would be made more useful if it could be configured to systematically provide prospective or real-time monitoring of adherence behavior. Routine monitoring of ART adherence could empower patients through timely feedback, and could offer healthcare providers actionable information for the delivery of targeted adherence support interventions. Related studies may include:
- Studies to test technology-assisted monitoring approaches that provide feedback loops to patients regarding their ART adherence, and triage patients demonstrating persistent non-adherence to adherence support interventions.
- Research to test technology-delivered or assay-based point-of-care ART adherence assessments to facilitate targeted delivery of interventions to individuals in need of adherence support.
- Studies to develop and test predictive models that use monitored ART adherence levels, patterns, and other factors to produce actionable information regarding the future likelihood that a given individual may experience viral failure.
Apart from drug concentrations, PrEP lacks a ready biomarker associated with behavioral adherence that is analogous to viral load in HIV treatment. PrEP prevention trial data have raised questions about the validity of adherence measures such as self-report and pill counts in trial settings. In the context of clinical care, feasible and valid approaches for monitoring PrEP adherence are needed to address clinical guidelines emphasizing regular adherence monitoring and to identify individuals needing additional support for adherence. There is an additional challenge of examining PrEP adherence concurrently with risk behavior, since PrEP will not have preventive utility unless its use appropriately encapsulates risk behavior. Priority research in this domain may include:
- Research that provides clinicians with feasible and effective methods for monitoring patient adherence to PrEP in open-label use.
- Studies that test technologies or assays that facilitate prospective or "real-time" monitoring of PrEP adherence.
- Research that examines patterns of PrEP adherence in relationship to patterns of risk behavior.